Soil release of polyester containing textiles through treatment with aminoplast resins in conjunction with acrylic emulsion polymers containing at least 20% acid calculated as acrylic acid



United States Patent SOIL RELEASE OF POLYESTER CONTAINING TEX- TILESTHROUGH TREATMENT WITH AMINO- PLAST RESINS IN CONJUNCTION WITH ACRYL- ICEMULSION POLYMERS CONTAINING AT LEAST 20% ACID CALCULATED AS ACRYLICACID Francis W. Marco, Spartanburg, S.C., assignor to Deering MillikenResearch Corporation, Spartanburg, S.C., a corporation of Delaware NoDrawing. Filed Aug. 4, 1966, Ser. No. 570,169

Claims. (Cl. 8115.6)

This invention relates to a process for treating a substrate to impart asoil release characteristic thereto, and to products produced thereby.Preferably, the present invention relates to a process for impartingsoil release to a textile substrate.

The genesis of synthetically produced textile fibers has brought about atremendous effort in the textile industry along numerous avenues. Therehas been much research effort directed to the improvement of thesesynthetic fibers per se, and improved blends of synthetically producedfibers with natural fibers, i.e., cellulosic fibers or keratinousfibers. Results of this research have been successful and the directionof research has been diverted fromthe synthetic polymer per se and/orblends of said polymers with other naturally occurring fibers. Ofrecent, fiber research has been directed towards improving physicalcharacteristics of fabric produced from synthetic fibers and/ or blendsof these synthetic fibers with naturally occurring fibers, and, morespecifically, to the physical characteristics and/ or enduranceproperties of garments produced from synthetic fabrics and/ or fabricproduced from blends of synthetic fibers and naturally occurring fibers.Tremendous effort has ensued towards achievement of a garment containingsynthetic and naturally occurring fibers such that creases in thegarment are very durable and are not appreciably affected by wear orcleaning processes. In other words, after repeated washings and/ or drycleaning, the creases remain in the garment in a substantially unalteredcondition and further treatment of the garment, i.e., pressing, is notrequired for maintenance of the crease. Likewise, much eifort has beenexpended towards the attainment of good wash-'and-wear fabric.

Additionally, further research has been directed to the attainment of agarment having improved soil release properties. Numerous of thesynthetically produced fibers that are presently being incorporated inblends with naturally occurring fibers have a propensity to accept andre- .t ain only grime and dirt. Accordingly, when the garment is beingworn the soil and/or oily material's accumulate on the garment andsettle in the fabric. Once the garment becomes soiled, it is thensubjected to a cleaning process for removal of the dirt and/or oilydeposits, and only a dry cleaning process will successfully clean thegarment. The cleaning process normally employed, however, is washing ina conventional home washing machine by the housewife. During a washcycle, it is virtually impossible to remove the soil and/or oily stainsfrom the garment and, secondly, assuming that the undesirable materialsare removed from the garment or a fairly clean garment is being washed,soil remaining in the wash water is redeposited onto the garment priorto the end of the wash cycle. Hence, when the garment is removed fromthe washing machine and subsequently dried, it has not been properlycleaned. Such a condition, heretofore unavoidable, is quitedisadvantageous in that the garment after being worn never again assumesa truly clean appearance, but instead tends .to gray and/ or yellow dueto the soil and/ or oily materials deposited and remaining thereon.Further use and washing of the garment increases the intensity of thegraying to the point that ultimately the garment is unacceptable forfurther Wear due to its discoloration. The process of the presentinvention solves the soiling problem as hereinafter described.

In attempting to solve the problem of soiling in the synthetic fabricsand blends containing synthetic fabrics, a substantial amount ofresearch has been conducted and numerous patents have issued as a resultthereof. None of these patents, however, disclose subject matter asrelevant to the problem as is instantly set forth herein. Strong basisof this fact is evidenced by the absence from the market of a productthat may be easily cleaned so as to remove soil and alleviateredeposition of soil from the wa'sh water. Anti-soiling research hasbeen directed along two general avenues, one of which utilizes inorganicmaterials and the second employing the utilization of organic materials.Set forth below is a brief summary of prior efforts.

U.S. Patent 2,999,774 to Schappel features the utilization of silicaparticles and a salt of a mul't'ivalent metal for the purpose ofrendering a fabric soil resistant. U.S. Patent 2,734,835 to Florio eta1. employs at least two hydrous stable metal oxides selected fromaluminum, si'l-ica, titanium, beryllium, cerium, cobalt, germanium,manganese, tin, zinc and zirconium. U.S. Patent 3,089,- 778 to Pierce etal. teaches the utilization of a water insoluble basic aluminum salthaving an ultimate particle size of less than 0.5 micron. U.S. Patent2,992,943 to Coover et al. while not purely related to inorganicmaterials is directed to prevention of dry soiling only. In other words,the Coover et al. treatment dictates the use of a watersoluble compound(an alkyl stitinate and an organic solvent) and therefore to obtain thedesired soil resistant properties only a dry cleaning process may beemployed.

The organic approach to the soiling problem of synthetic fibercontaining fabrics includes the following patents and their teachings.It should be noted, however, that some of the patents incorporated inthe following group are not per se directed to reducing the. soilingpropensity of the synthetic fiber containing fabric.

U.S. Patent 3,236,685 to Caldwell et al. renders a fabric antistatic andsoil-resistant by coating a fabric with a solution or solutionscontaining a polymeric acid defined as containing COOH, SO H and/ or POH groups. Additionally, a compound containing a polyol or a compoundhaving incorporated therein epoxide groups is included which underproper conditions reacts with the acid to form an ester. U.S. Patent3,152,920 also to Caldwell et al. is a complement of the above patentwherein, instead of reacting the polymeric acid with a polyol or anepoxide, the polymeric acid is reacted with the reaction product of apolyol and a polyisocyanate. U.S. Patent 3,125,405 to Gardon is directedto the manufacture of a permanent press garment. N-methylol acrylamideis applied to the fabric with a free radical acid catalyst and theN-methylol acrylamide is cross-linked with the cellulose molecule.

Additionally, extra monomers and polymers are as set forth in the patentwhich may be incorporated in the treating solution. U.S. Patent3,246,946 to Gardon likewise is directed to the production of durablepress garments. N- methylol acrylamide is employed in conjunction withone or more condensates of an aldehyde and a free radical acid catalystwhereby the reactants are crosslinked with the cellulose molecule. Extramonomers and polymers may be added to the treating solution. U.S. Patent3,090,- 704 to Collins et al. is directed to a terpolymer for render ingthe fabric soil resistant. The terpolymer consists of (1) a compoundhaving incorporated therein a crosslink ing component, (2) a compoundhaving incorporated therein an anionic component, e.g., an alkali metalsalt of an aromatic sulfonic acid, and (3) a compound having a componenttherein that contains a strong nonionizable, nonhydratable permanent orinduced dipole. US. Patent 2,876,141 to Matthews employs a solutioncontaining (1) mineral oil, (2) base cordage oil, (3) oleic acid, and(4) a cationic wetting agent, e.g., trimethylp-oleamidoethyl ammoniumsulfate in an effort to improve the soil resistance of the fabrictreated.

The above brief abstracts are set forth to provide an indication ofprior research effort directed to attaining a soil resistant fabric or afabric having soil release properties. The problem heretofore confrontedwith fabrics having incorporated therein synthetic fibers has been thatthe synthetic fibers while hydrophobic are oleophilic and thereforewhereas oil and grime may become embedded in the fiber, its hydrophobicproperties prevent water from entering the fiber to remove thecontaminates therefrom. The efforts of this invention have been directedto the modification of the properties of textile material comprisingpolyester fibers in such a manner that the soil and oily contaminatesmay be easily removed.

Additionally, by incorporating the process of the present invention withthat of a process to render a garment resistant to creasing, a garmentis produced that has both durable press and soil release properties. Inother words, the ultimate garment is a utopia for the onsumer and forthe housewife who is confronted with the problem of rendering thegarment clean for further wearing.

In view of the above comments it should be evident to one skilled in theart that the problem confronted has been that of rendering a garmentclean if the garment contains synthetic and/ or natural fibers asdescribed here in. Accordingly, by virtue of the teachings of thepresent invention, the problems historically present with the use ofgarments having incorporated therein both cellulosic fibers andsynthetically produced fibers are alleviated.

It is therefore an object of the present invention to provide asubstrate having soil release properties.

Still another object of the present invention is to provide a processfor treating a substrate whereby said sub strate easily releases soilwhen contacted with a detergent solution.

Still further another object of the present invention is to treat asubstrate in such a manner that after said substrate is soiled andsubjected to washing, less soil and grime from the wash water will beredeposited thereon.

A further object of the present invention is to provide a durable pressfabric having soil-release properties.

Another object of the present invention is to provide a process fortreating a fabric in such a manner that it has both durable press andsoil release properties.

Still another object of the present invention is to treat fabric in sucha manner that after a garment produced therefrom is soiled and subjectedto washing, soil and grime from the wash water will not be redepositedonto the garment.

Still further another object of the present invention is to provide atreatment for fabric such that garments produced therefrom will notbecome discolored due to repeated wearing and washing.

Another object of the present invention is to treat fabric in such amanner that a garment produced therefrom has excellent wash-and-wear andsoil release properties.

These and other objects may be readily seen from the following detaileddescription of the present invention.

Generally speaking, the present invention is directed to a process forimparting soil release and durable press characteristics to a textilematerial comprising linear polyester fibers which comprises applyingthereto an aminoplast textile resin, atextile resin catalyst and asynthetic acid emulsion polymer which is stable under the conditions ofapplication, and curing the textile resin. The polymer comprises atleast 20 weight percent acid calculated as acrylic acid, andthe.proportion of acid polymer solids on the textile material is fromabout 0.25 to about 5.0 weight percent based on the dry weight of thetextile material.

Soil removal ability is improved on any organic substrate comprisinglinear polyester fibers when the acid polymer is applied thereto.Suitable substrates comprising polyester fibers, which should not beconsidered as limiting, may be prepared from paper, synthetic polymers,cotton, wool, mixtures of the above, etc. Products made from thesematerials include without limitation, wall paper; synthetic wallcoverings; textile fabric wall coverings; lamp shades; automobile seatcovers; automobile upholstery, e.g., door panels, overhead liners, etc.;upholstery for furniture; clothing; apparel accessories, e.g., ties,fabric belts, scarves, hats, etc.; canvas products, e.g., tents, foldingcots, etc.; draperies; throw pillows; hassocks; sporting goods; fabricgarment bags and luggage; fabric handbags; fabric shoes or shoes madefrom synthetic materials; linens; book covers; mattress covers; stuffedtoys; hammocks; deck chairs, etc.

Textile materials are preferred substrates and those which can betreated according to the process of the invention are those comprisingpolyester fibers. The term textile material comprising polyester fibersthus comprises polyester fibers with other fibers within the abovedefinition, e.g., cotton, paper, linen, jute, fiax, regeneratedcellulose fibers, including viscose rayon, in the form of staple, yarnand fabrics. This invention is directed primarily and preferably topolyester and cellulosic containing textile fabrics either knitted,woven, or nonwoven, preferably woven. However, the advantages of thisinvention can the achieved by treating the fibers, yarns, or threadsemployed to produce these fabrics.

Moreover, and more specifically, the process of the present invention ispreferably used for treating textile materials containing both polyesterand cellulosic and non-cellulosic fibers, especially, if thenon-cellulosic fibers have minimum care characteristics of their own.For

example, the fabrics treated may be formed from a mixture of polyester,such as poly(ethylene terephthalate) and polyamide such aspoly(hexamethylene adipamide) or acrylic fibers, such aspolyacrylonitrile, and copolymers containing at least about 85% combinedacrylonitrile filaments or fibers, cotton or rayon. It should be pointedout, however, that textile material containing only non-cellulosicfibers such as those listed above is also within the scope of thepresent invention.

The soil-release properties of pure cellulosic fiber fabrics are muchbetter than those of synthetic fiber containing fabrics, e.g., polyesterfibers, in that, the synthetic polyester fibers are hydrophobic and thusprevent the ingress of water that is necessary for cleaning the fabricand also possess an electrical charge that attracts soil particles. Thepresent invention is therefore most primarily directed to fabricscontaining a substantial portion of synthetic polyester fibers.

An aminoplast textile resin will also be applied with the acid polymer.Very unexpectedly, it has been observed that when the textile resin andthe acid polymer are both applied to the textile material followed bysubjecting the material to textile resin curing conditions, improvedsoil release is realized.

Hence, the present invention is also directed to a process for treating.a textile material by applying thereto an aminoplast textile resin, atextile resin catalyst and a filmforming synthetic acid emulsionpolymer, said polymer containing at least 20 weight percent acidcalculated aslacrylic acid and effecting the formation of a film aroundthe fibers that make up the textile material and curing of the textileresin.

The term textile resin according to the present invention includes bothmonomers and polymers which when applied to a textile material andreacted under proper conditions undergo polymerization and/orcondensation and are transformed to the thermoset state. Textile resinsthat may be employed when practicing the present invention are theaminoplast resins. These nitrogen containing resins when applied to atextile material in the presence of a catalyst at temperatures of from130 C. to about 200 C. are transformed into the thermoset state. Theaminoplast resin condenses with the cellulose molecules and when vinylgroups are present in the aminoplast resin, it undergoes additionpolymerization with itself and also with the cellulose molecule ifirradiated. The cured textile resin on the textile material affords thetextile material a durable press and/or wrinkle resistantcharacteristic.

Exemplary of the aminoplast resins that may be employed according to thepresent invention are the urea formaldehydes, e.g., propylene ureaformaldehyde, dimethylol urea formaldehyde, etc.; melamineformaldehydes, e.g., tetramethylol melamines, pentamethylol melamines,etc.; ethylene ureas, e.g., dimethylol ethylene urea, dihydroxydimethylol ethylene urea, ethylene urea formaldehyde, hydroxy ethyleneurea formaldehyde, etc., carbamates, e.g., alkyl carbamateformaldehydes, etc.; formaldehyde-acrolein condensation products;formaldehyde-acetone condensation products; alkylol amides, e.g.,methylol formamide, methylol acetamide, etc.; acrylamides, e.'g.,N-methylol acrylarnide, N-methylol methacrylamide, N- methylolN-methacrylamide, N-methylmethylolacrylamide, N methylol methylenebis(acrylamide), methylene-bis(N-methylol acrylamide), etc.;haloethylene acrylamide; diureas, e.g., trimethylol acetylene diurea,tetramethylol-acetylene diurea, etc.; triazones, e.g.,dimethylol-N-ethyl triazone, N-N'-ethylene-bis dimethylol triazone,halotriazones, etc.; haloacetamides, e.g.,N-methylol-N-rnethylchloroacetamide, etc.; urons, e.g., dimethylol uron,dihydroxy dimethylol uron, etc., and the like. Mixtures of aminoplasttextile resins are also within the scope of the present invention.

Further exemplary of the textile resins within the scope of the presentinvention are those which conform to the following structural formulae.In each of the following formulae the variables may be selected asfollows:

R hydrogen, lower alkyl or residue of saturated or unsaturated aldehydeR hydrogen, lower alkyl or -CX-CR =CHR R hydrogen or methyl R hydrogenor lower alkyl R hydrogen, lower alkyl, or CHR OR at least one R beingCHR OR R lower alkyl or hydroxy alkyl R: hydrogen, hydroxyl or loweralkyl R: hydrogen, lower alkyl, alkylol or alkenol X: sulfur or oxygenwhere a is a whole integer from 1 to 6 The amount of textile resinapplied to the fabric is primarily determined by the ultimate use ofgarments or articles prepared from the fabric. Very small amounts of theresin will afford some improvement and large amounts even greaterimprovements, but the larger amounts of resin generally adversely affectthe hand of the fabric. Hence, the amount of resin employed ispreferably that which will afford good crease retention and flat dryproperties while not adversely affecting the hand. For the purposes ofthe present invention, the amount of textile resin in the pad bath mayvary between about 2 and 30%. Resin applied to the fabric should be inthe range of about 2 to 20% based on the dry weight of the fabric andpreferably in the range of about 4 to 9% Catalysts employed within thescope of the present invention depend upon the specific textile resinthat is applied to the textile material. For instance, if the textileresin has a functional group that is reactive under acidic conditions,then an acid catalyst is used. Likewise, when a functional group ispresent that is reactive under alkaline conditions, then a base catalystis used. Furthermore, both acid and base catalysts may be used when bothtype functional groups are present in the textile resin. In thisinstance, the catalysts may be added separately or together. When theyare added together, one must be a latent catalyst, i.e., one that willnot initiate its reaction during the opposite type reaction, but may beactivated subsequently under proper catalytic conditions.

The catalysts useful in activating the acid or base reactive groups arethose conventionally used to activate the reaction of textile resinscontaining the same group for reaction with hydroxy groups of cellulose.Preferably, latent acid or base acting catalysts are utilized,'that is,compounds which are acidic or basic in character under the curingconditions. The most common acid acting catalysts are the metal salts,for example, magnesium chloride, zinc nitrate and zinc fluoroborate andthe amino salts, for example, monoethanolamine hydrochloride and2-arnino-2-methyl-propanol nitrate.

The base acting catalyst preferably is a compound which does notinitiate substantial reaction between the base reactive group andhydroxy groups of cellulose under normal acid conditions, but doesinitiate substantial reaction under prescribed conditions, such aselevated temperature or some other activating means, as through use ofanother chemical compound. For example, an alkali metal sulfite can bepadded onto the fabric and be decomposed into strongly basic alkalimetal hydroxide by including small amounts of formaldehyde in the steamused for curing.

The latent base acting catalyst utilized herein preferably comprisesalkali-metal salts, such as alkali-metal carbonates like sodiumcarbonate, which is neutral to mildly alkaline, for example, pH of about8.5 on the fabric but decomposes at temperatures in excess of about 80C. to form the stronger base sodium oxide which will initiatesubstantial reaction at the elevated temperatures utilized duringcuring. Sodium carbonate may be utilized if desired since the pH in thefabric produced by this compound in normal conditions is generallyinsufficient to initiate the desired degree of reaction under normaltemperature conditions.

If fabrics containing a base reactive group are maintained at pH levelsabove about 10, however, degradation occurs, so that essentially neutralor mildly alkaline cata lysts are preferred when base reactive compoundsare utilized.

Additional base acting catalysts include potassium bicarbonate,potassium carbonate, sodium silicate, alkali metal phosphates, such assodium or potassium phosphates, barium carbonate, quaternary ammoniumhydroxides and carbonates, for example, lauryl trimethyl ammoniumhydroxides and carbonates and the like.

The amount of catalyst to be utilized is that conventionally used inactivating the reaction between textile resins and hydroxy groups ofcellulose, for example, up to about 15% by weight of an acid actingcatalyst in the application bath with the preferred range being fromabout 1% to about 7%. A preferred range for the base. acting catalyst isagain the conventional amount and is generally between about 0.2% toabout 16%, preferably about 2 to 16%. The amount of catalyst to beutilized will further depend in part on the temperature at which thereaction is conducted and the amount of catalyst consumed in thereaction. For example, when base catalysts are utilized and if a highlyacidic group is released during the reaction, the amount of base appliedto the textile material should be at least sufficient to provide anexcess of base in addition to that which is consumed by the highlyacidic group.

The term soil release in accordance with the present invention refers tothe ability of the fabric to be washed or otherwise treated to removesoil and/r oily materials that have come into contact with saidmaterial. The present invention does not per se prevent the attachmentof soil or oily materials to the fabric, but hinders such attachment andrenders the heretofore uncleanable fabric now susceptible to asuccessful cleaning operation. While the theory is still somewhat of amystery, soiled, treated fabric when immersed in the detergentcontaining wash water experiences an agglomeration of the oil at thefabric surface. This water is basic in nature and it has been determinedthat soil release is best realized in wash water that is basic innature. These globules of oil are then removed from the fabric and riseto the surface of the wash water. This phenomenon takes place in thehome washer during continued agitation, but the same effect has beenobserved even under static conditions. In other words, a strip ofpolyester/cotton fabric treated according to the process of the presentinvention and soiled with crude oil, when simply immersed in .adetergent solution will lose the oil without agitation. The oil justballs up on the fabric, dislodges therefrom, and rises to the surface ofthe solution.

An added feature of the present invention is the prevention of soilredeposition from the wash water. One of the greatest disadvantages ofthe synthetic polymers is the feature that even after removing the soilby washing, there is the continued danger that the soil will beredeposited onto the fibers from the wash water before the garment isremoved therefrom. It has been observed that the soil release ability ofthe presently treated fabric diminishes after repeated washings. Evenafter the ability to remove soil from the fabric has diminished,however, the observation has been made that the prevention ofredeposition of soil from wash water remains potent. This phenomenonlikewise is unexplainable, but it has been established that thetroublesome soil is negatively charged and presumably there remainsenough acid on the fabric to repel the negatively charged soil.

Numerous of the substrates that may be treated according to the processof the present invention may not be feasibly removed from theirenvironment and washed in a washing machine. Further, there are alsosubstrates that may be treated which when subjected to the action of awashing machine are adversely affected either in structure or in looks.Articles within these classes may still be easily cleaned in place orotherwise by scrubbing the soiled area lightly with a solution of acommercial detergent and water.

The soil release polymer of the present invention will also behereinafter referred to as an acid emulsion polymer. This acid emulsionpolymer may be selected from a large number of synthetically producedcompounds provided certain limitations are met. The acid polymeremployed advantageously is capable of forming a film around the fibersthat constitute the textile material. Softness of the film is important,for if the film is too hard, the hand of the textile material isadversely affected. Further the film must have hydrophilic propertiesand be at least partially insoluble in Water. The film, if watersoluble, would, of course, be easily washed from the fabric. Acidcontent of the film is likewise important and at least 10 weight percentof the acid polymer from which the film is formed must be acidcalculated as acrylic acid and preferably at least 20 weight percent.The results obtained from using acid polymers containing 10 weightpercent acid give improved results as may be seen from Table III. Forcommercial acceptance, however, these should preferably be at least 20weight percent acid in the soil release polymer calculated as acrylicacid. Again reference is made to Table III. It has further been observedthat all of the acid polymers that afford soil release have acarbon atomto acid group ratio in the repeat group in the range of 2:1 to 30:1, andthat an air dried film cast therefrom has a water of imbibition of atleast 89%.

synthetically produced acid emulsion polymers within the scope of thepresent invention may be prepared from any of the polymerizable organicacids, i.e., those having reactive points of unsaturation. Thesepolymers may be interpolymers of the acid and other monomerscopolymerizable therewith so long as at least 20 weight percent acidmonomer is present in the polymer. Exemplary of polymerizable acids thatmay be used, are acrylic acid, maleic acid, fumaric acid, methacrylicacid, itaconic acid, crotonic acid, cinnamic acid, polymerizablesulfonic acids, polymerizable phosphoric acids, etc. Monomers that maybe interpolymerized with the acids include any monomers capable ofcopolymerizing with the acids and which will not detrimentally affectthe film-forming properties of the polymer. Suitable monomers include,esters of the above acids prepared by reacting the particular acid withan alkyl alcohol, e.g., ethyl acrylate, methyl acrylate, propylacrylate, isopropyl acrylate, methyl methacrylate, ethyl methacrylate,2-ethylhexyl acrylate, butyl acrylate, etc.; alkyl fumarates, maleates,crotonates, cinamates, etc.; vinyl halides; monomers having vinylidenegroups; e.g., styrene, acrylonitrile, methylstyrene; substituted vinylmonomers, e.g., chlorostyrene;. butadiene, etc. In all of the polymersprepared from the above listed monomers, there must be at least 20weight percent acid calculated as acrylic acid. It should be noted thatvarious mixtures of the above polymers will work according to theprocess of the present invention and hence should be considered withinthe scope of the present invention. Furthermore, salts of the acidpolymers, e.g., sodium, potassium, lith ium, ammonium, etc., will affordthe desired soil release characteristics.

9 Examples of some of the synthetic acid polymers that may be usedaccording to the present invention are polymerization products of:

Some acid polymers work better than others, however, and these arepreferred. Examples of the preferred acid emulsion polymers include (1)copolymers of ethyl acrylate and acrylic acid that are prepared bypolymerizing a comonomer mixture of from about 50 to 80 parts of ethylacrylate and about 20 to 50 parts of acrylic acid; (2) copolymers ofpropyl or isopropyl acrylate and acrylic acid wherein the copolymers areprepared by polymerizing a monomer mixture of from about 40 to 57 partspropyl or isopropyl acrylate and about 43 to 60 parts of acrylic acid;(3) copolymers of butyl acrylate and acrylic acid prepared bypolymerizing a co-monomer mixture of from about 30 to 70 parts of butylacrylate and about 70 to 30 parts of acrylic acid; (4) copolymers of2-ethylhexylacrylate and acrylic acid prepared by polymerizing aco-monomer mixture of from about 10 to 40 parts of 2-ethyl hexylacrylate and about 60 to 90 parts of acrylic acid; (5) copolymerssubstantially identical to the ones listed above with the exception thatmethacrylic acid is substituted for acrylic acid and the esters aremethacrylates instead of acrylates; (6) a copolymer of ethyl acrylateand itaconic acid prepared by polymerizing a monomer mixture comprisingabout 70 parts ethyl acrylate and about 30 parts itaconic acid; (7)copolymers of the acrylic acid set forth above wherein the acrylates aresubstituted by methacrylates; and (8) terpolymers comprisingethylacrylate, acrylic acid and acrylamide prepared from monomermixtures of ethyl acrylate, at least 10 parts acrylic acid and up toparts acrylamide.

The acid polymers suitable for use in practicing the present inventionform a hydrophilic film upon drying and afford soil release ability atthat point. For unknown reasons, further treatments and/or ingredientswill enhance the soil release ability of the substrate. If the substratehaving the acid polymer thereon is subjected to to textile resin curingconditions, the durability of the soil release ability is enhanced.Likewise, the presence of a textile resin catalyst during the textileresin curing conditions further improves soil release ability. Stillfurther, the soil release finish is much more lasting on a substratewhen the acid polymer is subjected to textile resin curing conditions inthe presence of an aminoplast textile resin. It is known that the filmcovers the hydrophobic synthetic fiber contents of the textile materialwithout any reaction therewith. What is not understood, however, is thedurability of the soil release characteristic. While it is known thatthere is some reaction between the acid polymer and the textile resin,the reaction mechanism is very speculative. Furthermore, there may besome crosslinking between the cellulose molecules and the acid polymeror there may be just an enhanced physical bond between the textile resinand the acid polymer above and beyond their reactivity.

Soil release polymers, like the textile resins, give some improvement atvery low levels on the fabric. Accordingly, as the amount of soilrelease polymer is increased, the ability of the fabric to release soilincreases. Thus, the upper limit on the amount of soil release polymeris determined by economics and resulting adverse effects on the fabric,e.g., the hand of the fabric. Furthermore, practically speaking there isa set range of soil release polymer dictated by commercial success.

The acid polymers, are emulsion polymers containing varying amounts ofsolids, normally in the range of about r to 50 weight percent. Thepolymer emulsion should be present in the pad bath or other applicationmedium in the range of about 2.5 to 40 weight percent. Otherwise stated,there should be from about 0.25 to 5.0 weight percent of acid polymersolids applied to the substrate, based on dry weight, and preferably 1.0to 1.5 weight percent.

The bath used to impregnate the textile material according to thepresent invention is not limited to including only the possibleingredients heretofore mentioned, e.g., textile resin, textile resincatalyst and acid polymer. In addition, other ingredients may beemployed such as, for example, emulsifying agents, wetting agents,softeners, etc., and numerous other compounds that enhance the physicalcharacteristics of the fabric. The bath may be applied to the substratein any suitable manner. For instance, padding of the bath onto fabric ispreferred because of ease of operation at that particular stage of thedevelopment. The ingredients may be sprayed on as liquids; the substratemay be treated with vapors of the compounds if convenient; the substratemay be dipped, etc.

In general, the applicator system is adjusted to provide from to 100weight percent wet pickup by the fabric from the pad bath. Preferably,however, it has been determined that best results are obtained byproviding a wet pickup of from to weight percent from the pad bath.

When the aminoplast textile resin is applied to the substrate, e.g.,textile material, along with the acid polymer they may be simultaneouslyapplied from the same pad bath. Simultaneous application is not requiredthough and the same results may be realized by first applying the soilrelease polymer followed by separate application of the textile resinand curing of the textile resin. Insofar as separate application isconcerned, however, where the textile resin is applied first and curedand the soil release polymer is added separately thereafter, initialsoil release ability is outstanding, but not nearly so durable as thesimultaneous application or the separate addition where both textileresin and soil release polymer are present during curing of the textileresin.

According to the desires of the individual, and the dictates of theultimate product, separate or simultaneous application of the textileresin and the soil release polymer may be employed. 'For instance, whentreating a textile fabric which is to be converted into work clothes, itwould be desirable to have as durable a finish as possible so that thesoil release properties will be as long lasting as possible. In thissituation, either a simultaneous addition or a separate addition wherethe soil release polymer is added first would be desired. On the otherhand, where the ultimate article of manufacture is not one that will bewashed or cleaned on a weekly basis, for instance, the desirableproperty might possibly be to have a very superior initial soil releaseproperty. An example would be upholstery for automobiles, seat covers,wall coverings, etc. For these items it may be more desirable to firstapply the textile resin and separately after curing of the textile resinapply the soil release polymer.

Advantages afforded by the process of the present invention areavailable for substrates treated in almost any form, e.g., films,sheets, fibers, yarns, threads, fabrics or the ultimate product, e.g., agarment, etc. The presensitizing embodiment, i.e., the textile resintreatment, when employed is most advantageously conducted on substratesin the fabric, etc., form.

Garments made from the fabrics treated according to the process of thepresent invention require no additional steps than normal for thepreparation of the conventional durable press garments. In other words,the garment may be folded and pressed on conventional equipment, forexample, a Hoffman press. The pressing cycle utilized is standard in theindustry and generally involves pressing of the garment for a shortperiod of time, followed by a curing operation in an oven.Alternatively, the garment may be set in a desired configuration underhot, dry conditions, such as by hot pressing without steaming, forexample, at temperatures of up to about 200 C. for as long as necessaryto cure the resin.

In general, the aminopl-ast textile resin employed may be selected fromseveral general types. According to the type resin selected, one of thefollowing processes may be generally followed to achieve the novelgarments produced by the present invention. In each type procedure, themethods of application and order of application of textile resin, soilrelease polymer, catalysts, etc., may be varied as described supra.

TYPE I (1) Apply textile resin having one type functional group, textileresin catalyst and soil release polymer to fabric.

(2) Dry fabric at temperature that is insufficient to initiate catalysisof the textile resin.

(3) Make garment from fabric.

(4) Press garment to produce creases where desired.

(5) Subject garment to temperature sufiicient to catalyze and cure thetextile resin.

TYPE II (1) Apply textile resin having more than one type of functionalgroup, textile resin catalysts for each type functional group and soilrelease polymer to fabric.

(2) Subject fabric to conditions whereby one type of functional groupreacts and remaining functional groups remain dormant.

(3) Prepare garment from the fabric.

(4) Press creases where desired in garment.

(5) Subject fabric to conditions whereby the remaining functional groupsare reacted with the cellulose.

TYPE III 1) Apply textile resin having more than one type of functionalgroup, one type being sites of ethylenic unsatu-ration, a textile resincatalyst and a soil release polymer to the fabric.

(2) Dry the fabric at temperatures such that the textile resin catalystremains dormant.

( 3) Subject the fabric to irradiation.

(4) Make a garment from the fabric.

(5) Produce desired creases in the garments.

(6) Subject the garments to textile resin curing conditions.

In each of the above types of procedures, the ultimate curing of thetextile resin may be accomplished prior to the manufacture of thegarment whereby a good Weish-and-wear fabric having soil releaseproperties is pro duced.

Procedures of Types 1, II and III, as is evident, relate to the processof the present invention being applied to a textile material to affordsaid textile material soil release and durable press or wash-and-wearcharacter istics. Otherwise than above shown, the acid polymer, textileresin catalyst, etc., are just applied to the desired substrate anddried, subjected to textile resin curing conditions, etc., according tothe specifications described herein.

The drying temperatures that are insufiicient to initiate the catalysisare, of course, dependent upon the particular catalyst being employed.In general, however, the drying step is conducted at a rate ofapproximately 10 to yards per minute at temperatures ranging from about225 to 300 F. preferably in a tenter frame. The drying temperature rangeoverlaps to some degree with the curing temperature range set forthbelow. When drying in the overlapping portion of the drying and curingranges, it is important that there be no premature curing of the textileresin. Time is the prime variable and when drying the substrate in thehigher end of the drying temperature range, care must be taken to avoidheating the substrate for a time sufiicient to initiate catalysis thatwould at least partially cure the textile resin.

Irradiation techniques may be employed according to the process of thepresent invention when an aminoplast resin having ethylenic unsaturationis applied to the textile material. An insulating core transformer,operated at a potential varying between one hundred thousand electronvolts and five hundred thousand electron volts may be successfully usedto irradiate the textile material. Such a transformer is commerciallyavailable from High Voltage Engineering Corporation, Burlington, Mass.The amount of ionizing irradiation necessary according to the presentinvention is at least 32 electron volts for each ion pair formed. Thusirradiation of 32 volts and above is effective. Both high energyparticle and ionizing irradiation areuseful according to the presentinvention. The preferred dosage of irradiation according to the presentinvention is in the range of one thousand rads to one hundred megarads,a rad being the amount of high energy irradiation of the type whichresults in energy absorption of one hundred ergs per gram of absorbingmaterial. More preferably, however, the irradiation dosage ranges from0.5 to 5 megarads.

Curing of the textile resin is accomplished by subjecting the textilematerial having the textile resin thereon to conditions such that thecatalyst initiates a crosslinking reaction between functional groups ofthe resin and hydroxyl groups of the cellulose in the textile materialand converts the resin to the the-rmoset state. When a percent syntheticfabric is treated, the resin adheres to the material and is converted toa thermoset state. Temperature'is the prime mover and generally atemperature in the range of C. to about 200 C. is sufi'icient. Thecuring medium that supports the necessary temperature may be anysubstance that is inert to both the fabric and'the ingredients appliedthereto, e.g., hot air, steam, etc. In the instance where the textileresin possesses two different types of functional groups, there areactually two curing steps, the first being conducted at a temperaturelower than the second and insuific ient to initiate the second type ofcatalysis, e. g., a first partial curing step to initiate alkalinecatalysis and a subsequent curing step to initiate acid catalysisandalso convert the resin to the thermoset state.

The duration of the various processing steps varies diversely with theparticular ingredients employed. In each situation, however, thetreatment time is that necessary to sufiiciently cause reaction of and/or curing of the textile resin.

Trademarks and abbreviations used throughout the specification andexamples are set forth below.

Dacron T 54: A polyester fiber manufactured by E. I.

du Pont de Nemours & Co.

Dacron T-56: A polyester fiber manufaitured by E. I.

du Pont de Nemours & Co.

Dacron T-64: A polyester fiber manufactured by E. I. du Pont de Nemours& Co.

Fortrel: A polyester fiber produced by Celanese Fiber Company Kodel: Apolyester fiber manufactured by Eastman Kodak Company Orlon: Apolyacrylonitrile fiber manufactured by E. I.

du Pont de Nemours & Co.

Acrilan: A polyacrylic fiber manufactured by Chemstrand Corporation, adivision of Monsanto Company Nylon 20: A polyamide fiber manufactured byE. I.

du Pont de Nemours & Co.

NMA: N-methylol acrylamide (60% aqueous solution) DHDMEU: Dihydroxydimethylol ethylene urea (50% aqueous solution) SRP: Copolymer of 70parts ethyl acrylatez30 parts acrylic acid (25% aqueous emulsion)Profine: Mixture of glycerol monostearate, and polyethylene glycolmonostearates R-l: A commercial uron resin manufactured by Rohm & HaasSyn-Soft A-20: A polyethylene emulsion (20% solids) manufactured bySylvan Chemical Co., Pacolet, S.C.

Alipal CO-436: An ammonium salt of a sulfated alkyl phenoxypoly(ethyleneoxy) ethanol manufactured by General Aniline and FilmCorporation Triton X200: A sodium alkyl aryl sulfonate (30% solids)manufactured by Rohm & Haas Triton X202: A sodium alkyl aryl sulfonate(28% solids) manufactured by Rohm & Haas The following examples are notintended to limit the scope of the present invention, but merely toprovide direction to one skilled in the art. It should be noted that aconcurrent y filed companion application claims subject matter hereinplus at least 1% of an ethoxylated alkyl phenol. Several of thefollowing examples include at least 1% ethoxylated alkyl phenol, but areincluded only to show soil release ability in their particularenvironment and not to show the improvement in soil release contributedby the presence of the ethoxylated alkyl phenol. Unless otherwisestated, parts are by weight.

Example 1 A pad bath solution was prepared by dispersing in water thefollowing ingredients: 17% N-methylol acrylamide (60% aqueous solution);4% Zinc nitrate (50% aqueous solution of (Zn(NO -6H O); 3% Syn-Soft A-20and 0.25% Alipal 'CO-436. The above composition was padded onto samplesof Dacron/cotton (65/35) fabric to 50% wet pickup and the fabric driedon a tenter frame at 13 yards per minute at a temperature of 250 to 280F. Moisture content of the dried fabric tested The dried fabric was thensubjected to irradiation in an insulated core transformer manufacturedby the High Voltage Engineering Corporation of Burlington, Mass.

Fabric was passed through the irradiation equipment at 40 yards perminute at a setting on the transformer of 500 kilovolts and 15milliamps, the fabric being arranged in a 5 pass festoon duringirradiation to produce a dosage of 2 megarads. Several pairs of mensslacks were then prepared from the treated fabric and pressed on aHoffman press in the conventional manner and then pressed on a hot-headpress at a cycle of 5 seconds steam, seconds bake and 5 seconds vacuum.The pressed slacks were then suspended from a continuously movingconveyor in an oven and cured for minutes at 325 F. After severalwashings, the pressed slacks retained all creases unimpaired.

Example 2 The procedure followed in Example 1 was repeated with theexception that 100% cotton fabric was treated rather than the 65/35Dacron/cotton. After curing and repeated washing, the creases in thecotton slacks remained as originally pressed into the garments.

14 Example 3 Example 1 was again repeated with the exception that a 100%Dacron fabric was treated. Again, after repeated washings, creases inthe slacks remained unimpaired.

Example 4 The following pad bath was prepared: 25% dihydroxy dimethylolethylene urea; 4.3% magnesium chloride (MgCl '6H O); 3% Syn-Soft A-20;0.2% Triton X-200; and 68.5% water. The above emulsion was padded onto aDacron/Cotton 35 fabric at 50% pickup and the fabric was dried at atemperature ranging from 250 to 275 F. on a tenter frame. Moisturecontent of the dried fabric tested 5.6%. Mens slacks were prepared fromthe treated Dacron/ cotton fabric and subjected to the identicalpressing and curing condition set forth in Example 1. Creases in theslacks remained unimpaired after several washes.

Example 5 Example 4 was repeated with the exception that a 100% cottonfabric was treated instead of the 65/35 Dacron/ cotton. After repeatedwashings, the creases in the slacks remained unimpaired.

Example 6 Example 4 was again repeated, but a 100% Dacron fabric wastreated in lieu of the Dacron/cotton blend. Creases produced during thepressing cycle of the procedure were very durable to repeated washings.

Example 7 Samples of Dacron/ cotton 65/ 35 fabric were treated with apad bath emulsion of the following formulation: 20% N-methylolacrylamide (50% aqueous solution); 10% emulsion copolymer of ethylacrylate:acrylic acid (:30); 5% magnesium chloride catalyst; and 65%water. A pad bath prepared according to the above recipe was padded ontothe Dacron/ cotton fabric at 50% pickup and the fabric dried attemperatures ranging from 200 to 280 F. to achieve a fabric moisturecontent of approximately 5%. The dried fabric was then given anirradiation dosage of two megarads and converted into mens slacks.Slacks prepared from the treated Dacron/cotton fabric were then pressedand cured identically to those procedures described in Example 1. Afterseveral washes, the creases produced in the slacks by the Hoffman pressremained substantially unimpaired, indicating that the presence of theethyl acrylatezacrylic acid copolymer did not adversely affect thedurable press characteristics of the treated fabric.

Example 8 The procedure described in Example 7 was repeated with theexception that cotton fabric was treated instead of 65/35 Dacron/cottonfabric. Similar durable press results were obtained.

Example 9 Slacks were made from 100% Dacron that was treated accordingto the procedures described in Example 8. After repeated washings thecreases in the slacks were virtually as sharp as when they wereoriginally produced in the garment before curing in the oven.

Example 10 A pad bath was prepared according to the followingformulation: 24% dihydroxy dimethylol ethylene urea (50% aqueoussolution); 10% copolymer of ethyl acrylate:acrylic acid (70:30); 5% zincnitrate 6% Profine; 0.2% Triton X202; and 54.8% water. The pad bathaccording to the above recipe was padded onto Dacron/cotton 65/ 35fabric at 50% pickup. The fabric was then dried at temperatures rangingfrom 245 to 280 F. on a tenter frame. Several pairs of mens slacks weremade up from the treated Dacron/ cotton (65/35) fabric after whichcreases were produced and the garments cured according to the proceduresdescribed in Example 1. After several washings the durability of thecreases was evident by their inertness to the washing operation.

Example 11 Cotton fabric was substituted for the Dacron/cotton fabric inExample 10 and the procedures thereof were repeated. Creases in theslacks were unaffected by the repeated washings.

Example 12 The Dacron/ cotton fabric of Example 10 was replaced by 100%Dacron and Example 10 was repeated. Several washings showed no effect onthe creases in the Dacron slacks.

Example 13 A pad bath was prepared according to the following recipe:10% copolymer of ethyl acrylatezacrylic acid Group A were stained with aNo. 6 crude oil and subjected to one home washing in a Kenmore automaticwasher, using one cup of Tide, a commercial detergent, and a Watertemperature of 140 F. The slacks in Group B were first washed five timesunder wash conditions identical to those for Group A. The Group Bslacks, after their fifth wash were then stained with a No. 6 crude oiland subjected to one further wash under the same wash conditions as setforth above. After each wash, the slacks were dried in a Kenmore dryerat a temperature of from about 150 to 165 F. for approximately minutes.After the designated number of washings, the residual oil stains in theslacks were compared to a set of standards having numerical ratings from1.0 to 5.0, 1.0 being very poor and 5.0 representing virtually completeremoval of the stain. Ratings for the tested slacks are set forth belowin Table I and are indicative of the soil release property of thefabrics. Controls for the various fabrics are also included andrepresent slacks made from the fabric that was un- 20 treated; and theslacks were just pressed as per normal procedures.

TABLE I.SOIL RELEASE DATA FOR COTTON, DACRON/GOITON AND DACRON FABRICSSoil Release Rating Sample Fabric Treatment Control 1 1 Wash Control 1 5Washes 1 Dacron/cotton (/35) NMA 1.5 1.7 2 Cotton NM- 1.8 1.9

Dacron NMA 1.0 1.0 4 Dacron/cotton (65/35) DHDMEU 1. 1.5 1.7 5 CottonDHDRTEU 1.7 1.8 6 Da DHDMEU 1.0 1.0 7 Dacron/cotton (GS/3s SRP and NMA 12. 7 4. 5 4.0 8. Cotton NMA and SR? 3. 5 4.2 3- 9 9 Dacron NMA and SR?1.4 4.0 10 Dacron/cotton (05/35) DHDlVIEU and SRP 3.3 3-6 Cotton DHDMEUand SRP. 3.3 3. O Dacr DHDMEU and SRP 3. 1 2.0 Dacron/cotton (65135 SR14. 5 4.0 0t SR1. 4.6 3.0 Dacron SRP 3.5 1.6 Dacron/cotton (GS/35)....SRP 2 4.2 4. 17 Cotton SRP 2 4.5 2.9 Dacron sar 2.0

1 No treatment was rendered to control samples.

2 N0 catalyst in pad bath. (:30); 5% zinc nitrate (Zn(NO -6H O); andwater. The above emulsion was padded onto Dacron/cotton (65/35) fabricat 50% pickup and the fabric dried at a temperature ranging from 250 to275 F. Mens slacks were prepared from the treated fabric and pressed andcured as per the procedures defined in Example 1.

Example 14 Example 13 was repeated except that cotton fabric was used inplace of the Dacron/cotton fabric.

Example 15 Example 13 was repeated except that 100% Dacron was treatedin lieu of the Dacron/cotton fabric.

Example 16 Example 17 Example 16 was repeated except that a 100% cottonfabric was treated in lieu of the Dacron/ cotton fabric.

Example 18 Example 16 was repeated, but using a 100% Dacron fabric.

Example 19 .Two sets of slacks were taken from each of the groupstreated, as described in Examples 1-18. In each case, the slacks wereidentified by the number of the example, and further identified bysufiixes A and B. Slacks in From the data set forth in Table I thefollowing conclusions may be drawn: (a) soil release ability forDacron/cotton and Dacron fabrics is substantially improved when the soilrelease polymer is added, (b) the finish afforded thefabric by the soilrelease polymer is enhanced when the soil release polymer is deployedwith a textile resin and a textile resin catalyst and the treated fabriccured; (c) soil release ability of each of the fabrics is reduced whenonly the textile resin is employed to afford the fabric with a durablepress property, whereas the addition of the soil-release polymer morethan compensates for the reduction brought about by the textile resinabove.

Test washes for obtaining soil release data were conducted using thecommercial detergent Tide, marketed by Procter & Gamble. This particulardetergent does not however, contribute specifically to the soil releaseability. Numerous of the commercial detegents were rated against onecommercial detergent as a standard. There was only a slight differencein these detergents noted, so one cup full of any of them should performsatisfactorily.

Example 20 To evaluate the breadth of the present invention regardingthe fabrics which may be improved as to soil release, a number offabrics were soiled with a No. 6 crude oil, washed one time in a Kenmoreautomatic washer with one cup of Tide at a wash water temperature of F.The fabric was then dried for approximately 40 minutes at a temperatureof from about to about F. and rated against the soil release standardsreferred to above. Samples of the same fabrics were padded with anemulsion containing 12% dihydroxy dimethylol ethylene urea; 10%copolymer of ethyl acrylate:acrylic acid (70:30); 5% zinc nitrate (Zn(NO-6H O); and 73% water. The samples were then cured in a conventionalgarment cure oven for 15 minutes at C. Each TABLE IL-SOIL RELEASE DATA 5Fabric Untreated DHDME U Control and SRP Dacron T54 1. 4 4. Dacron T-56-2. 8 4. 2. 4 4. 2 4. o 4. 0 3. 5 4. 2 1. 3 4. 4 1. 2 4. 0 3. 8 4. 3 4. 04. 2 3. 4 4. 6 3. 6 4. 4 l 5 2. 5 3. 5

From Table II it is evident that with the exception of viscose, everytype fabric treated showed improvement in soil release ability.Moreover, the sample of viscose fabric was not resin treated and aspointed out supra resin treatment reduces the soil release ability ofthe fabric. Hence, were the fabric resin treated so as to afford durablepress properties to the fabric, then some soil release improvement wouldbe evident. Magnitude of improvement of soil release with the variousfabrics was dependent primarily on the original soil release ability.For example, in the case of cotton as compared to any of the Dacrons,the improvement is not nearly so great, for the cotton originally hadmuch better soil release than the Dacron. Improvement is shown, however,in every instance.

Having determined that a copolymer of ethyl acrylate: acrylic acid(70:30) afforded superior soil release properties to the variousfabrics, it was encumbent to establish the limits of operability of thesoil release polymers. Such efforts have been expanded in two ways.First the composition range of the ethyl acrylate:acrylic acid copolymersystem was investigated, and secondly, other polymer systems were testedfor their soil release ability. Table III sets forth soil releaseperformance for various ethyl 40 acrylate:acrylic acid compositions andTable IV sets forth soil release performance of various other copolymersand terpolymer systems.

Example 21 A series of copolymers of ethyl acrylate and acrylic acidwere prepared having varied proportions of acrylate and acid. Each ofthese polymers was then divided into two parts, A and B. Part A of eachpolymer was padded onto Dacron/cotton (/35) fabric and the other partused to make films. The pad baths containing the various ethylacrylate-acrylic acid polymers had the following formulation: 10% ethylacrylate-acrylic acid polymer; and 90% water.

After drying the impregnated fabric, and curing the fabric, samples ofthe fabric were stained with a No. 6 crude oil and washed and furthersamples were first washed five times, then stained and washed once more.After the staining and washing, each sample was rated for soil releaseability by comparison with the standards discussed supra. Results of thesoil release tests are reported 60 in Table III. Part B of each polymersample as stated above was made into a film. After the film was cast andair dried, it was then immersed in water for 16 hours to determine thewater of imbibition thereof. Water of imbibition is reported for eachpolymer as percent water absorbed after 16 hours per weight of the film.Water of imbibition data is also reported in Table III.

Additionally, pad baths were prepared containing the followingingredients: 18% N-methylol acrylamide; 10% ethyl acrylate:acrylic acidpolymer; 4% zinc nitrate; and 68% water. The ethyl acrylate:acrylic acidpolymer composition varied in the pad baths prepared as identified in.Table III. After padding the emulsion onto Dacron/ cotton (65/35)fabric the fabric was dried at temperatures ranging from 250 to 275 F.,subjected to an irradiation 18 dosage of 3 megarads and cured for 30minutes at 130 C. The fabric was then stained, washed and ratedidentically to the above fabric where only the soil release polymer wasapplied. Data is reported in Table III.

TABLE III SOIL RELEASE ABILITY AND WATER OF IMBIBITION DATA FOR ETHYLACRYLATE; ACRYLIC ACID COPOLYMERS Polymer Composition Stain and Water ofStain Wash Imbibition Ethyl Acrylic (a)/ (b) (a)/(b) Wt. percentAcrylate Acid 1 Wash 5 Washes Increase percent percent 100 0 1.5/1.51.5/1.8 49 90 10 2. 5/2. 0 2.0/2.2 89 20 2. 7/2. 0 2.0/3.2 167 70 304.4/4.0 3. 0/4. 0 312 60 40 3.7/3.4 3.0/3. 6 50 50 3.5/3. 0 3.0/3. 2 3070 4. 5 3.0 20 80 3. 8 3.0 10 3.8 3.0 0 4. 0/2. 8 3.0/3.0 UntreatedControl 2.6/1.5 (c) 2.7/1. 7 (c) Water soluble.

(a) Polymer only padded onto fabric. (b) Resin, catalyst and polymerpadded. I (c) Resin treated only (n-methylol acrylamlde) Study of dataset forth in Table III indicates that an acrylic acid content of lessthan 10% is undesirable for promoting soil release from theDacron/cotton fabric. Moreover the water of imbibition datacorresponding to the polymer compositions provides an excellent criteriafor determining whether the polymer will successfully afford soilrelease properties to a fabric when the polymer contains more than 10%acid. When the water of imbibition of the film falls below 89%, thenthere is insufficient water absorption to remove the oily soil from thegarment during washing.

Example 22 A series of polymers were padded onto a Dacron/cotton 65/ 35fabric in the following pad bath formulation: 16% N-methylol acrylamide;10% polymer; 4% zinc nitrate catalyst; and 70% water. The variousformulations were padded onto the fabric and the fabric was dried,irradiated, cured, stained, washed and rated as previously described.The specific polymers employed in the pad bath formulation and the soilrelease data are reported in Table IV.

TABLE Iv.-s.0IL RELEASE DATA FOR VARIOUS POLY- MERS PADDED ONTODACRQN/COTTON (65/35) FAB- RIC ALONG WITH RESIN AND CATALYST Soilrelease rating,

Example 23 In further attempting to define the polymers thatsuccessfully afford soil release, the water of imbibition was determinedfor films prepared from a group of polymers. The films were cast, airdried, and immersed in excess water for a period of 16 hours. Waterabsorbed by the film was then determined and is reported in Table V asweight percent increase. Also, each of the polymers, as set forth inTable V was incorporated into a pad bath of the following recipe: 10%polymer, 18% N-methylol acrylamide, 4% zinc nitrate catalyst (Zn(NO -6HO) and 68% water.

Two samples each of Dacron/cotton (65/35) fabric were padded with theformulations prepared, dried and cured. Each sample was then stainedwith No. 6 crude oil and each set of samples given the 1 and w'ashes asdescribed in Example 1. After washing, the stains were rated against thesoil release standards. Data is reported in Table V along with water ofimbibition.

TABLE V.SOIL RELEASE AND W'ATER OF DJBIBITION DATA FOR ACID POLYMERS Infurtherance of establishing the operability of the soil release polymersof the present invention, a more quantitative test was followed toindicate soil release properties of the treated fabric.

is vastly superior to the conventional durable press fabric in releasingsoil during a conventional wash cycle.

Example Earlier in the specification, information is set forth relevantto the order of application of the textile resin and the soil releasepolymer. Tests were conducted to determine criticality, if any, of theorder of application and/or whether there is any synergism between thevarious compounds in the pad bath. Dacron/cotton (65/35) fabric Was usedin each test. Pad baths included aqueous emulsions of the materials setforth in Table VII. In cases where drying, irradiation an-d/ or curingare indicated, procedures were followed as set forth in Example 1. Threesets of samples were prepared in each instance, one of which was stainedwith No. 6 crude oil and washed as described supra, one of which waswashed five times, stained and washed once more and the third of whichwas washed ten times, stained and given a further wash. These data, ofcourse, provide good readings on both initial soil release ability anddurability of the soil release finish. After the final wash, each of thesamples was compared to the soil release rating standards and given anumerical rating of 1.0 to 5.0, 5.0 being complete removal of the stain.Data are recorded in Table VII.

TABLE VII.-STUDY OF SYNERGISM BETWEEN NiAJOR AND BATH OONSTITUENTS ANDORDER OF AP- PLICATION OF TEXTILE RESIN AND SOIL RELEASE POLYMER SoilRelease Rating After W sl Sample Pad Bath Cure Pad Bath Irtra- Cure WashPad Bath Cure a res a ion F=10% copolyrner of ethyl acrylatezacrylicacid (70:30) 25% emulsion).

G=2.3% Syn-Fae N-905. 183=24% dimethylol dihydroxy ethylene urea.

Example 24 A sample of Dacron/cotton (65/35) fabric was padded with apad bath emulsion comprising 18% N-methylol acrylarnide (60% aqueoussolution); 10% copolymer of ethylacrylate:acrylic acid (70:30); 4 .3%zinc nitrate solution of Zn(NO -6H O); 2% Syn-Fae N905 and 4% Profine at50% pickup. The fabric was then dried on a tenter frame at 13 yards perminute at temperatures ranging from 240 to 270 F.; subjected toirradiation by the method described in Example 1 and cured by theprocedures prescribed in Example 1. A second sample of Dacron/cotton(65/35) fabric having been treated by a conventional method to impartdurable press properties was compared to the above treated fabric. Boththe conventional durable press fabrics were soiled with a radioactivesebacious soil, then washed once in a conventional automatic washingmachine with one cup of All, a commercial detergent in wash water havinga temperature of 105 F., and tested to determine the amount of soilremaining on the fabric. Data is reported in Table VI.

TABLE VI.-RADIOACTIVE SOIL RELEASE DATA ON SOIL RELEASE TREATED-DURABLEPRESS DAC-RON/COTTON (1050/?)(figjsfslhlTREATED DURABLE PRESSDACRON/COT- Conven- Durable tional Press Durable and Soil Press,Release, Percent Percent Solling Tests: Sebacions Soil Pickup 5.9 5. 7Soil Retention, 105:

Nash in ALL" 82 25 The above data shows positively that the fabrictreated to have both durable press and soil release characteristics Thedata recorded in Table VII indicate that best overall results areobtained when the textile resin and soil release polymer aresimultaneously applied to the fabric or when the soil release polymer isapplied first followed by the textile resin, curing as shown by Samples2, 3, 5, 6 and 10. On the other hand, where the soil release polymer isadded last and cured after the textile resin has already beeen cured,there is excellent initial soil release, but durability is adverselyaffected, as shown in Samples 1, 4 and 9. These data further show alsothat when the soil release polymers are cured in the presence of thetextile resin and catalyst, durability of the soil release ability isperceptibly improved. As mentioned before, it is believed that thisphenomenon is brought about by some reaction between the textile resinand soil release polymer during curing of the resin. The mechanism isnot, however, known. In fact, the durability might be afforded by aphysical bond or a combination chemical reaction and physical bond.

Example 26 The following experiment was conducted to determine theability of fabrics treated by the process of the present invention torepel deposition of oily materials and grime from dirty wash water. Thefollowing pad bath was prepared and labeled formulation A:24% R-l, 6%magnesium chloride catalyst, 3% Profine, 2.3% Syn-Fae N- 905 agent and64.7% water. A second pad bath labeled formulation B, was preparedidentical to the above-identified formulation with the exception that10% of a soil release polymer, a copolymer of ethylacrylatezacrylic acid(70:30), was included and the amount of water was reducedproportionately, i.e., (54.7% present). These formulations were paddedonto Dacron/ cotton (.65 35) shirt- 21 ing. The fabric was then driedand precured at 325 F. for 1 /2 minutes, after which shirts weretailored from the fabric. The shirts. were then labeled A (formulationA) and; B (formulation B) and'subjected to five home washings in. aKenmore automatic washer using one cup of Tide and wash water of 140 F.Prior to placingshirts A' and B in the same washer, a quantity of oiland dirt was put into the water. After the five washes, theshirts weretested in a Hunter color meter manufactured by Hunter AssociatesLaboratory, Inc., 5421 Briar Ridge Road, McLean, Va., to determine thecomparative soil pickup by the shirtsin the washer.

The Hunter instrument employs a polychromatic light source andmatchedset of barrier-layer photoelectric cells. One photoelectric cellis illuminated directly by the light source while the otherphotoelectric cell is illuminated by light reflected from a fabricsample. Measurements are made of the degree of unbalance, existingbetween the photoelectric .cells, from the current generated by thephotoelectric cell receiving direct illumination and the currentgenerated by the photoelectric cell receiving fabric .refiectedillumination. Values may be read from digital dials onthe device ofthree visually-uniform color scales, the three, readings being L, a and17 wherein:

L =measures lightness and varies from white to zero for black;a=measures redness when greeness when minus; b=measures yellowness whenblueness when minus.

100 for perfect plus, ,gray when zero, and

plus, gray when zero, and

A value for whiteness (W) may be computed from these values by means ofthe following formula:

Likewise additional shirts labeled A and B were sent out to a commerciallaundry and tested for whiteness after commercial washings without soiladdition. Data are reported in Table VIII.

was dried as described above. All of the fabric samples were thencompared to a set of stained standards; The standar'ds show differentdegrees of a NoEG'crude oll "stain and are rated from 1.0 to 5.0.Arating of 120 indicat'esalm'ost'no removal of. the stain and 5.0indicates virtually complete removal ofthe stain. After comparing thefabrics with the standards, eachwas'given a numerical'rating. These dataappear in Table IX.

,TABLE 1X.sorL RELEASE DATAusrNo DACRON/CO'I TON FABRIC AND A COP'OLYMEROF ETHYLACRYLATE: ACRYLIC ACID (70:30) 1 Soil'Belease Rating SampleTreatment Stain and 5 Washes, 1 Wash Stain and J Wash A ';."Dry; "3.83.5 B Dry and Cure 4.2 4.3 Untreated Control 2.7 2.8

Data in Table IX indicate that the Dacron/cotton control that wasuntreated,'then stained and washed did not release the crude oil nearlyaswell as both Samples A and B that were treated with the soilreleasepolymer.

What is claimed is:

1..A process for imparting soil release and durable presscharacteristics to a textile material comprising linear polyester fiberswhich comprises applying thereto an aminoplast textile resin, a textileresin catalyst and a synthetic acid emulsion polymer which isstable'under the polymer is prepared by emulsion polymerizing a.monomeric mixture comprising an acrylic ester and an acrylic acid. TABLEVIII.SOIL REDEPOSITION DATA FOR WHITE SHIRTS Treatment Wash 'L' a' -b WShirt A l -1 Oily 83. 4 +2. 5 +3. 1 74. 1 Shirt 13 R-l-I-SRP do 88. 6+2. 7 87.4 Shirt 1 Normal commerc l +1. 7 99. 3 Shirt B R1+SRP do +1. 6102.0 Control None ,7

From the data in Table VIII is therefore evident that all of the shirtslost some of their whiteness after the washings. Shirt B in both theoily washes and the commercial washes retained their whiteness betterthan Shirt A in each type wash. This positively indicates that less soilwas deposited from the wash water onto Shirt B, the shirt having thesoil release polymers applied thereto.

Example 27 A pad bath formulation was prepared from the followingingredients: 10% copolymer of ethylacrylatezacrylic acid (70:30) (25%solids), 90% water, and padded onto Dacron/cotton (65/35) fabric at 50%pickup from the pad bath. The fabric was then dried in a tenter frame at10 yards per minute at a temperature ranging from 250 to 275 F. Afterdrying, the fabric was divided into two separate lots. A and B. Fabricin lot B Was further subjected to textile resin curing conditions (325F. for 15 minutes). Both A and B lots were then subdivided into twofurther groups, A1 and A-2 and B-1 and B-2. Fabric from A-1 and B1 werestained with a No. 6 crude oil and washed one time in a Kenmoreautomatic washer with one cup Tide, a commercial detergent marketed byProcter & Gamble. Wash Water temperature was 140 F. After washing, thefabric was then dried for approximately minutes at a temperature ofabout 150 to 165 F. Fabric A-2 and B-2 were first subjected to fivewashings as defined above; stained with No. 6 crude oil; and then washedone more time. After the last wash the fabric 4. The process as definedin claim 1 wherein the acid polymer is prepared by emulsion polymerizinga monomeric mixture comprising about 50 to parts of an acrylic ester andabout 20 to 50 parts of an acrylic acid.

5. The process as defined in claim 1 wherein the textile material is apolyester/cellulosic textile material, the textile resin is selectedfrom the class consisting of N- methylol acrylamide and dihydroxydimethylol ethylene urea, the acid polymer is prepared by emulsionpolymerizing a monomeric mixture comprising an acrylic ester and anacrylic acid, and the textile resin on the textile material is heated toa temperature in the range of about C. to 200 C. for about 1 to 30minutes.

6. A textile material having soil release and durable presscharacteristics, prepared according to the process of claim 1.

7. A cellulosic containing textile material having soil release anddurable press characteristics, prepared according to the process ofclaim 5.

8. A process for imparting soil release and durable presscharacteristics to a textile material comprising linear polyester fiberswhich comprises applying thereto an aqueous dispersion comprising (a)about 2 to 30 percent of an aminoplast textile resin, (b) about 2.5 to40 percent of a film-forming synthetic acid polymer which is stableunder the conditions of application, said polymer being prepared byemulsion polymerizing a monomeric mixture comprising about 50 to 80parts ethyl acrylate and about 20 to 50 parts acrylic acid, and (c) upto 15 percent of a catalyst selected from the group consisting of zincnitrate and magnesium chloride; and heating said textile material at atemperature in the range of about 130 C. to 200 C. for about 1 to 30minutes, whereby a film is formed on said textile material.

9. A process-for imparting soil release and durable presscharacteristics to a polyethylene terephthalate/cotton (65/35) textilematerial which comprises:

(a) applyin thereto an aqueous dispersion consisting essentially ofabout 2 to 30% of an aqueous solution of a textile resin selected fromthe class consisting of N-methylol acrylamide and dihydroxy dimethylolethylene urea, about 1 to of an aqueous solution of a catalyst selectedfrom the group consisting of zinc nitrate and magnesium chloride, about2.5 to 40% of an aqueous emulsion of a film-forming synthetic acidpolymer prepared by polymerizing a monomeric mixture comprising anacrylic ester and at least weight percent of an acrylic acid, and water;said aqueous dispersion being applied to the textile material in therange of to weight percent of the textile material proportion of acidpolymer solids on said textile material being from about 0.25 to about5.0 weight percent based on the dry weight of the textile material;

(b) drying the textile material at a temperature in the range of about225 F. to 300 F. for a time insufficient to initiate curing of thetextile resin; and

(c) heating the textile material at a temperature in the range of aboutC. to 200 C. for a time sufii cient to cure the textile resin.

10. A process for imparting soil release and durable presscharacteristics to a textile material comprising linear polyester a-ndcellulosic fibers, which comprises applying thereto N-methylolacrylamide, an acid textile resin catalyst and a synthetic acid emulsionpolymer which is stable under the conditions of application, subjectingsaid textile material to high energy irradiation to eilect additionpolymerization of the vinyl group of said N-methylol acrylamide withitself and with the cellulose, and heating said textile material toreact the methylol group of said N- methylol acrylamide with the hydroxygroups of the cellulose under the influence of said acid catalyst, saidacid emulsion polymer comprising at least 20 weight percent acidcalculated as acrylic acid and the proportion of acid polymer solids onsaid textile material being from about 0.25 to about 5.0 weight percentbased on the dry weight of the textile material.

References Cited UNITED STATES PATENTS 2,725,308 11/1955 Nickerson8-1163 X 2,731,364 1/1956 Reibnitz 8-1163 X 2,754,280 7/1956 Brown etal. 811S.6 X 2,755,198 7/1956 Stewart 8-116.3 X 2,804,402 8/1957Williams 8-1163 X 2,810,624 10/1957 Wardell 8-1163 X 2,868,748 1/1959Frazier et al. 8-115.6 X 2,977,665 4/1961 McElrath 8-1163 X 2,987,4216/1961 Sherwood 117-139.4 3,011,917 12/1961 Dreisbach et a1. 117-13953,049,446 8/1962 Goldstein et al. 8-1163 X 3,079,279 2/1963 Van Loo8-1163 X 3,125,405 3/1964 Gardon 8-1163 3,125,406 3/1964 Herman 8-11633,152,920 10/1964 Caldwell et al. 117-1388 3,236,685 2/1966 Caldwell etal. 117-1388 3,246,946 4/ 1966 Gardon 8-1163 OTHER REFERENCES Stillo etal.: Tex. Res. 1., vol. 27, pp. 949-961 (1957).

Mazzeno et al.: A.D.R., p. 299-p. 302, May 5, 1958.

Nuessle et al.: Tex. Res. 1., vol. 33, pp. 146-160 (1963).

Walsh et al.: Tex. Res. 1., vol. 35, pp. 648-654 (1965).

Peper et al.: A.D.R., vol. 54, No. 21, p. 36-42, Oct. 11, 1965.

NORMAN G. TORCHIN, Primary Examiner.

I. TRAVIS BROWN, Examiner.

J. C. CANNON, Assistant Examiner.

11mm STATES PATENT or has CERTIFICATE OF CORRECTION Patent No. 3,377,249April 9, 1968 Francis W. Marco It is hereby certified that error appearsin the above numbered patent requiring correction and that the saidLetters Patent should read as corrected below Column 1 line 50 "only"should read oily Column 9 line 61 cancel "to" Column 12 line 72"manufaitured" should read manufactured Column 16 line 6 "their" shouldread the Column 18 TABLE III first second, third fourth and fifthcolumns line 3 thereof, "80" "20" "Z 7/2 .0" "2 0/3 2" "167" should read80 2O 3 7/3 0 3 0/3 2 and 167 same TABLE III same columns line 4 thereof"70" "30" "4.4/4 .0" "3 .O/4 O" "312" should read 70 30 4 3/4 0 3 0/4 0and 312 Columns 19 and 20 TABLE VII in the footnote line 3 thereof, "X=43% zinc ntirate (Zn[NO 3 6H O) should read X=4 3% zinc nitrate (Zn (N0 2oHzO) Column 21 line 63 "lots should read lots Column .22 line 9"DACRON/COT" should read DACRON/COT- Column 23 lines 22 to 25 cancel"proportion of acid polymer solids on said textile material being fromabout 0 25 to about 5 0 weight precent based on the dry weight of thetextile material and insert and being stable under the conditions ofapplication;

Signed and sealed this 11th day of November 1969 (SEAL) Attest:

EDWARD M.FLETCHER,JR. WILLIAM E SCHUYLER, JR. Attesting OfficerCommissioner of Patents

1. A PROCESS FOR IMPARTING SOIL RELEASE AND DURABLE PRESSCHARACTERISTICS TO A TEXTILE MATERIAL COMPRISING INEAR POLYESTER FIBERSWHICH COMPRISES APPLYING THERETO AN AMINOPLAST TEXTILE RESIN, A TEXTILERESIN CATALYST AND A SYNTHETIC ACID EMULSION POLYMER WHICH IS ABLE ISSTABLE UNDER THE CONDITIONS OF APPLICATION, SAID POLYMER COMPRISING ATLEAST 20 WEIGHT PERCENT ACID CALCULATED AS ACRYLIC ACID AND CURING THETEXTILE RESIN; THE PROPORTION OF ACID POLYMER SOLIDS ON SAID TEXTILEMATERIAL BEING FROM ABOUT 0.25 TO ABOUT 5.0 WEIGHT PERCENT BASED ON THEDRY WEIGHT OF THE TEXTILE MATERIAL.